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What are the pros and cons of coal as a fuel source?

Coal has long been valued for its high-energy content, and ancient civilizations would use it as a source of heat. When early steam engines were in use, they were generally powered by burning coal. Coal plants are fairly simple to build; a coal-burning fire heats water, and the steam created turns large turbines. While natural gas is almost as cheap as coal, China and other energy-hungry nations prefer coal plants.\nHowever, coal also releases a tremendous amount of carbon dioxide when it burns, and many developed nations are phasing it out as a result. However, China and other nations lack th..

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What happens if you receive the wrong blood type?

Blood used for a transfusion as well as the blood of the person receiving the transfusion undergoes a "type and cross match" test to determine compatibility, according to the National Center for Biotechnology Information. This greatly minimizes transfusion rejection, but even in this case, donor blood can contain antigens that are not routinely typed; this could be incompatible with the recipient's blood if it contains antibodies that target them.\nAccording to WebMD, some people bank their own blood in advance of surgery to minimize further the risk of receiving the wrong blood or reject..

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Why is the tip of my nose always cold?

Hypothyroidism should be ruled out when a cold nose is experienced along with being tired and having diminished concentration. Having a cold nose may also be the result of a subnormal body temperature, which when accompanied with chills, can indicate the presence of the common cold, according to the University of Oregon.

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How long is a Martian year?

At a distance of 141 million miles, Mars is the fourth planet away from the Sun, after Mercury, Venus and Earth. It is the second-smallest planet after Mercury, measuring at about half of Earth's diameter and containing about one-tenth of Earth's mass. It has two moons, and its surface resembles that of Earth more than that of most other planets. Mars experiences temperature extremes of -225 to 60 degrees Fahrenheit.

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Why does alcohol evaporate faster than water?

Alcohol can also form hydrogen bonds, but the carbon atoms in its molecules are unable to form such strong connections with each other. This lack of cohesion between carbon atoms allows alcohol molecules to move past each other relatively easily, while water's strong internal attraction creates a resistance to evaporation. This is why water remains liquid from 0 up to 100 degrees Celsius, while most compounds have a much narrower thermal range for their liquid phases.

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What are the characteristics of a cold front?

As the cold front approaches, the atmospheric pressure drops. It reaches its lowest along the front line and then suddenly increases. Observers also notice a change in the wind direction, usually from the southerly direction to the northwesterly in the United States. The approaching front brings brief showers that turn into thunderstorms as the front passes. In the wake of the front, these storms transform into showers before the weather clears.\nThe cold air mass often travels along the Earth's surface. At the bottom of the front, air moves much more slowly than air at higher elevations ..

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When is the brain fully developed?

The National Institutes of Health study found that the parts of the brain that are necessary for restraining risky behavior are not fully developed in teenagers. This explains why many teenagers are reckless drivers, have poor judgement skills and exhibit poor deductive reasoning skills. As individuals reach adolescence and teen years their brains are around 80 percent of the way developed, according to Children's Hospital in Boston.

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Do people shrink as they age?

People shrink as they age because the vertebrates in the spine lose fluid and flatten. Over the years, the arches of the feet flatten, causing a person to be a little shorter. Most people lose muscle mass in middle to later life, and that affects posture. The more a person slouches, the shorter he or she appears. In order to prevent age-related shrinking, regular exercise is necessary. Workouts geared toward core strengthening and those that work the legs and hips are important. Foods containing calcium and vitamin D also help.

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What is the function of the gallbladder?

The gallbladder is a pear-shaped pouch that is located underneath the liver. According to Healthline, eating too much fatty foods can result in the accumulation of cholesterol, bilirubin and bile salts, forming gallstones. When the gallstones block the bile duct, a surgery requiring the removal of the gallbladder is often required to treat the gallstones.\nOtherwise healthy people can live without a gallbladder because the bile that the gallbladder normally stores can be rerouted and directly released into the small intestine, notes Everyday Health. Harvard Medical School notes that an individ..

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What parts can you find on a human lung diagram?

Other parts of the respiratory system that may appear on a lung diagram include the airway and muscles used for respiration, states InnerBody.com. Human respiration involves taking in the oxygen in air through the different sections of the airway passage, which includes the mouth, nostrils, pharynx, larynx and trachea. From the trachea, or windpipe, air enters each lung through two branch-like tubes called bronchi. Each bronchus subdivides into smaller, branch-like parts called secondary and tertiary bronchi, which divide further into much smaller branches called bronchioles.At the end of the ..

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